"Radical Feminist" is the only part of the term that everyone agrees is not pejorative.

It is a real branch inside feminism, which lots of women identify with, and it doesn't mean what most people think it does.

Here: https://en.wikipedia.org/wiki/Radical_feminism

For some reason I cannot recall, a friend of mine had me read a bunch of proper radfem terf blogs back in like, 2010. I remember being impressed with the coherence of their worldview, even if it, uh, was not flattering.

Men were all inherently bad, penis-in-vagina sex was inherently rape, lesbians were good, trans-women were infiltrators and trans-men deserters.

"Radical feminism" is a branch of feminism. It is not used as a pejorative in the acronym.

You can say "gender essentialist" if you feel that TERF is too loaded, but it boils down to the same thing; it's a position that denies identity rather than accepting it.

It's only pejorative in the sense that it attempts to accurately describe the motives of a set of individuals who aren't comfortable with the way those motives are widely regarded. In that sense it's about as pejorative as "racist".

That is the danger of interpreting technical jargon without having the technical background. It will get you in trouble when you are talking about software just the same as when talking about science.

It might be loaded with denotation outside of the scientific community, but the word “radical” has some various scientific meanings, as other commenters have noted.

I think "trans-exclusionary conservative feminist" would be way more pejorative to the feminists in question.